Electromagnetic relay



y 1,641,256 Sept. 6, 1927 1. ERICKSON ELECTROMAGNETIC RELAY Filed Dec. s1, 91g

]z'zuEnZm" Jahn Erzcksnn l 6&4. lim? In thedrawings,

'Planted sept. e, 1927.v i

Q UNITED sTATEs APATENT [ol-Fica JOHN' aarcxsorr. `or'- cmcaao',n.nmo1s, assioma, artesana: assremnrs, ro

- aurona'rrc `Timun.'

appunti@ mea meenam a1, ma. serial n. 345,548. l

" My invention relateslin nml a electra magneticrelays .and-has or its object theprovisionof a relay having a, variable time constant; and more especially, a relay having avariable time constant which is adjustable between` much wider limits than are the well known types of slow acting relays now in common VThe preferred means' used to. attain this and other useful objects will bedescribed fully hereinaten'reference being had to the accompan 'ng drawing. l

1 shows a relay of my improved type connected for use in o eratingl a meter a predetermined time -af lr itsLcircuit is closed; Figure 2 shows Vanother modification of the relay which is used in combination with a differential relay to hold a circuit openfor a certain definite time interval.

Referring -to Fig. 1 the operation of 1 the relay may be briefly described as follows:

When the circuit of the rela 2 is closed by the contact 'device 3, the re ay is energized and closes its contact springs 4 and-5. The outside-contact spring has a rod 6 which isattahed to it b any suitable means, as for example, by so ering, which carries an adjustable weight 7. When the contact springs arevclosed the weight 7 begins to' vibrate rapidly, and rapidl interrupts the.

circuitL of` 'the meter MV W ich was closed when theco'nta'ct lspriuggfs 4- and 5 irst came into engagement with each other. The vmagnet-of the-meter is of high impedance and 'consequently does not fully energize so as-to attract itsarmature until-theweight 7 has stopped vibrat' -I have found by ex riment that'with t is arrangement I can clay the o ration of the meter as much as five secon s, and the riod of dela adjustable by re4 ating the stro e of the relay armatureand also to some extent b y moving the weight 7 up and down on the rod 6.

Y One of the applications in which Il have used this form of my invention is in connection with a." master switch of the general t pe shown .in the U. S. Patent to Keith 1go. 1,185,510, granted May 30, 1916. In a master switch of this type when all the outgoing trunk lines are busy, the master` switch is in continuous o ration. It is desirable in order to keep a c ose check on trac conditions to use a meter in connection with each master switch in order to register thenu'mmeter M will is readily'v murale nw., orcmcaco, minors, a' conroaa'rroir or Immv gucrnonoxn'nc amr.

ber of times the several groups of trunk lines become busy.' 'In using m improved relay the contact device 3 may bemounted-upon the starting relay-of the master switch which relaywis necessarly energized whenever the master switchis operating. The operation of the starting relay when-'the master switch moves the line switch plungers from one trunk to the next'in its ordinary operation of preselecting idle trunks does not close the circuit of relay 2 lon enough to permit the meter to register; an the longer closure of the circuit'of relay 2`Y causedby the locking up ofthe,I master switch starting relay whilel the master switch operating 'spring is being retensioned by the solonoid is still not long J'enough to cause the meter Ato'register. However, when allthe trunks are busy the master switch will operate continuously and the f starting relay will remain'energized while it is yoperatin thereby ensuring thatv the ally be operated to register. In Fig. 2 1 have shown a modification of the invention which will be easil understood. .The purpose of the embo ent of ducea'p'rolon'ged opening of the circuit extendm over conductor 20 whenever the relay` 10 1s energized. The operati-on is asfollowsz' When the circuit of relay 10-is closed at contact devices 21 it attracts its armature and closes contact springs '12and 13.

By this operation a circuit is completed through the two windings of the differential ed by vibrations of the wei ht 17. When relay 10`is rstenergized, t erefore, the dif ferential relay 11 is unbalanced and is op erated to attract its armature and separate contact springs 18 and 19. As soon asthe weight 17 has ceased vibrating contact sprln 14 and 15 remain closed and the circuit rough both its windings being new closed continuously, differential relay 11 will retract its armature and again close contact springs 18 and 19.'- Regulation of the 'time lnterval of the dierential relay is accomplished by adjusting the wei ht 17 on rod 16, and by regulating the ength of stroke of the armature of relay 10.

In adjusting the relays in both of the forms shown herein, Figs. 1 and 2, wide adjustments of the time constant are accomthe invention shown in this figure is to pro- 1 pushed by 1re" using the stroke of 'the relay armatures 'frequencies ofthe vibrations 4and w ile it alters to some'extent the duration of a series, of vibrationsit is of 4use chieily in adjusti ing the frequency to the `natural period of the devce'which has to be operated. For

example, in Fig. ,-1 the vibrations `of the weight 7 must be so fast that the short imulses of current sent through` the lmeter are msuicient to fully energize its operating r magnet. In case a meter or relay havin lower impedance or a lighter armature whic would respond more quickl is substituted `for-'the meter M the wei ht would have to be movedp higheron't e rod 6 toproduce vibrations of higher frequency in ,order to prevent the operation of such 'meter or relay.

Havin described Amy invention what I desire to ave securedand protected by Letters Patent will be pointed out in the appended claims.

What I claim as my invention is 5 1. A relay having contact springs, means for l,closing said sprin when the relay is energized, and a'weig t attached to one of said -springs to cause the same to vibrate and. dela the permanent closure of said sprin s IW ile said relay is energized.

2. relay havin circuit controlling contact springs, a weig t attached to one of said sprin to cause'the same `to vibrateand dela t e permanent closure of said springs w ile said relay is energized.

3. Arelay having contact springs for'closing'a circult, and means for causing one of .sa1d 's rings to rapidly vibrate andinter- I rupt t e contact while the relay remains energized.

4. yA relay having contactv members ,-for closing a circuit when the rela is energized, a weight attached to one o said contact members to cause the same to vibrate when therelay is energized, said member vibrating with constantly diminishing amplitude,

he ad]ustment of the weightsA -by'moving them .up and down chan es the illinois, this 24th day of and means for adjusting the said weight to r late the time consumed in diminishing t e amplitude ofvvibration.

5. A relay.v having circuit controlling springs, said relay when energized causing its armature to be permanently attracted, and additional means on said relay for o'pening `said circuit controlling springs and for premeans on Asaid arm for delaying the permitn ent closure Vof ,said circuit controlling springs for a predetermined interval after the armature is attracted. v

8. A relay having a pair of normali o en contact sprmgs, an armature for sai re ay effective when the same is energized to close said springs, and means on one of said springs for delaying the permanent closure of said springs for a predetermined eriod after the continued energization o said relay.

9. In combination with a relay havinga pair of contact springs andan armature for operating them, of a,4 member attached to said srings set in motion by the actuation of sai armature and eifective to delay the permanent operation of said springs until after said armature has been in an operated position for a definite riod. y

Signed -by me at C ica o, Cook County,

ecember, 1919.

' JOHN ERICKSON. 

